Knowledge

RWDI recently announced an equal partnership with Thornton Tomasetti on a new, high-performance damping solution for tall buildings: Hummingbird. This innovative technology will be available through a new firm called Hummingbird Kinetics.

RWDI and Thornton Tomasetti shared this news at the Council on Tall Buildings and Urban Habitat International Conference, which took place in Australia from October 30 to November 3, 2017.

This week, RWDI CEO Michael Soligo talks about Hummingbird Kinetics and about the role Hummingbird technology will play in RWDI’s damping systems practice.

What is Hummingbird?

Hummingbird is an innovative new damping technology – a tuned liquid column gas damper (TLCGD) – that can be distributed throughout a building instead of being installed in a single location. It is exciting because it can be a very effective and economical solution for projects where it is the right fit.

Why is it significant that this is a joint venture?

We’ve worked with Thornton Tomasetti to realize some of the most ambitious structures in the world – with their team providing structural engineering services, and our team consulting on wind engineering and damping systems. On both sides there’s deep expertise and a track record of innovation. Clients building tall and supertall buildings will benefit from the combined strength our two firms bring to Hummingbird Kinetics.

What are the origins of the Hummingbird?

A version of tuned liquid column gas damper (TLCGD) technology originated at NASA. They’d developed a new rocket for sending humans into space – but they found that this launch vehicle was susceptible to vibrations that were potentially very dangerous for humans. To mitigate those vibrations, NASA came up with something called Fluid Structure Coupling (FSC) Technology. As it turns out, this technology could be adapted to fulfill a range of very useful applications on Earth. This new venture, Hummingbird Kinetics, has worked with NASA to adapt the technology for use in buildings and bridges. The Hummingbird system combines water-filled pipes and external air springs, similar to an FSC device that NASA developed for one of their own test buildings; the external air spring allows us to tune the water’s behavior – and, in turn, dampen building vibration – with extreme precision.

What are the technical advantages the Hummingbird?

Compared to traditional liquid-tank dampers of equivalent performance, the Hummingbird needs less liquid mass in order to be effective. As a result, it provides an affordable, compact, flexible and easy-to-maintain alternative to slosh tanks and pendulum dampers for new buildings – all without compromising high performance. Less mass means a whole range of benefits: the damping system can be supported by a lighter and less expensive structure; it can be retuned in response to changes in a structure over time; and it can be installed in existing buildings that have vibration-related problems without the need to upgrade the structure to support a large additional load.

Left: an existing tuned mass damper; right: a Hummingbird system installed in a space of the same dimensions. Credit: Thornton Tomasetti/Pierre Ghisbain

Another advantage of this technology is these pipes can be distributed in various spots in the upper floors of a tall building; together they provide the same damping performance as a single large liquid damper concentrated in a central location. That makes a huge difference because having more flexibility about where you put your damping equipment means you can maximize available space at the top of buildings, where the value of the real estate is the greatest.

What will this new technology mean for RWDI clients?

It depends on the client – that’s the whole idea. We’ve earned our leadership position in the wind engineering and damping systems world by making our clients’ goals our own. That includes their engineering imperatives, their architectural ambitions and their business objectives. The Hummingbird is the newest tool in a toolbox we’re continually expanding and innovating on. We keep pushing our technical capabilities forward precisely so we’ll have in hand – or be in a position to develop – the optimal solution for every client and every project.

In some situations, the Hummingbird will be the optimal solution considering the performance, design and economic requirements. On other structures a customized tuned mass damper will be the best fit. The bottom line is clients come to RWDI because they trust that we’ll guide them to both the most cost effective and technically efficient solution based on the latest innovations and engineering know-how.

The first Hummingbird system was installed in a high rise in Brooklyn, New York last year. To learn more about the technology and how it’s applied, visit Hummingbird Kinetics.